Year Invented: 2014
Status: Basically a prototype. Sort of like the movie, but not really. They only work on metallic surfaces, so sidewalk surfing is out of the question.
Smartwatch With Precise Weather Forecasting
Apple Watch running 'Dark Sky' app
Company: Apple & The Dark Sky Company
California, as per this quote from the start of Back To The Future: Part II:
Marty: Alright Doc, what's going on, huh? Where are we? When are we?
Doc: We're descending towards Hill Valley, California at 4:29pm on Wednesday October 21st 2015.
The date was already personal and memorable to Doc, because it was the date he invented time travel:
Doc: Say, you wanna see the signing of the declaration of independence, or witness the birth of Christ. Here's a red-letter date in the history of science, November 5, 1955. Yes, of course, November 5, 1955.
Marty: What, I don't get what happened.
Doc: That ...
Hill Valley is in California, Pacific time with daylight savings (UTC-0700),
so the moment of truth is
The following 1885 railroad map, appearing in Back to the Future III (and listed here as a prop), shows that Hill Valley is located in northern California in the Sierra Nevada mountains:
(As @RoyalCanadianBandit points out, the DeLorean ...
It is not mentioned directly in the movie, but there is a piece of the DeLorean referred to as a "wormhole emitter" in the majority of quote-unquote "official" technical drawings/schematics/etc.
Let us assume the bright light/distortion that appears in front of the car is "the wormhole" - then it follows that the DeLorean has to drive through the wormhole; ...
According to the Q&A Commentary with Robert Zemeckis and Bob Gale, Back to the Future Part II Blu-Ray, 2010, the description of 2015 was not meant to be accurate. In the commentary, Zemeckis says (quoted by Wikipedia):
"For me, filming the future scenes of the movie were the least enjoyable of making the whole trilogy, because I don't really like ...
An in-universe explanation with a bit of math makes it all clear:
A Delorean DMC-12 is 4216 mm long. When travelling at 88 mph, the car then travels its own length in 4216mm/88mph = 107.2 ms. So this is how long the time-travelling wormhole-thingy that opens in front of the car has to be open, or alternatively the minimum time the flux capacitor is actually ...
Some nice speculations here, but according to producer and co-writer Bob Gale, they only picked it because it was a memorable number. On the Back to the Future blu-ray (probably the DVD too), if you go to the "Extras" menu and turn on "Q&A commentary with director Robert Zemeckis and producer Bob Gale", then play the movie with the audio from the Q&A,...
I would say ~19 days as listed out below:
BTTF 1 Total ~8.5 days
Marty goes to the Doc's house in the morning. He blows out the windows. Marty meets his friend, scientist Dr. Emmett "Doc" Brown, late that night in the parking lot of a deserted shopping mall,
Doc enters the date November 5, 1955, the date he came up with the concept of the flux ...
He tried to fix the DeLorean:
I set myself up as a blacksmith
as a front while I attempted to repair the damage
to the time circuits. Unfortunately, this proved impossible because suitable replacement parts will not be invented until 1947.
He wouldn't have sent the letter if he thought he could fix the DeLorean. He would have only sent the letter ...
He accidentally altered time into a timeline in which he did not exist in 2015.
Old Biff altered the events of time and as such possibly endangered his own future. As you state, Old Biff makes his earlier self a rich and insanely powerful man, basically owning all of Hill Valley.
In a deleted Scene from the movie, that can be ...
When Doc finally believes and sees the DeLorean and the real flux capacitor, the first thing he says is, “It works!! I finally invented something that works!”
None of his inventions have been successful before, so he has no reason to believe Marty when Marty opens with the claim that the time machine he came in was invented by Doc.
Also, the second piece ...
In the 4th draft of the screenplay, dated Oct 1984, the experiment takes place at 1AM:
MARTY: What's up, Doc?
BROWN: One a.m., right, Marty? You're gonna be there, right? Twin Pines Mall.
MARTY: Yeah, right.
This is definitely from before shooting started -- at this point, "Suzy" had not yet been renamed "Jennifer". Therefore, it was ...
The earliest such car that I am aware of is from the 1965 issue of Strange Tales that introduced SHIELD and inducted Nick Fury into their ranks. You can see in the images on this page that the wheels turn sideways and function as jet engines.
I've not found any indication why the script says 1:15 but we can infer a few reasons in-universe
Doc Brown was a very precise man (or a geek in modern vernacular). Remember the exactly 25 minutes slow clocks in the opening of the movie? The specific time was in keeping with the character being notably eccentric.
The mall parking lot was virtually ...
Doc probably "sent" at least one earlier letter.
Knowing Doc, he probably wrote Marty a letter as soon as he found paper to write on and cash to pay for it. But his chosen method of delivery was... quite slow. As such, he could have gone to Western Union at any time and simply tell them "Hey, you know that one letter I gave you to deliver 70 years from now? ...
The flux capacitor is powered by Mr. Fusion. You can see it on the back of the DeLorean in the following photograph. We can assume Doc put some appropriate items into it (such as food and other materials like at the end of Back to the Future or beginning of Back to the Future Part II) and they then just need to get the DeLorean up to 88MPH which is done ...
The book A Match Made in Space is introduced in the movie with this dialogue:
Biff: Mr. McFly, Mr. McFly, this just arrived, oh hi Marty. I think
it's your new book.
Lorraine: Ah, honey, your first novel.
Since Biff describes it as George's new book, this implies its publication date was 1985. And since it was his first novel, George wouldn't have ...
In the 1964 novel Chitty-Chitty-Bang-Bang, by Ian Fleming (yes, the guy that also brought us James Bond) the car actually does have the wheels turn flat to create a hovercraft effect for traveling over water:
CCBB, Ch. 6 Marooned:
And do you know what? I bet you can’t guess! All four wheels, pointing
fore and aft as all car wheels do, had turned and ...
Biff's actions at the dance in Back to the Future were significantly affected by Marty's presence in 1955. Being repeatedly humiliated, including having $300 worth of damage done to his car when it was filled with manure, left him really, really angry. Presumably, it was because of his particularly nasty attitude that night that he ultimately assaulted ...
The film's novelisation indicates that the Libyans didn't die. They were trapped inside the kiosk (in the crash) and were eventually arrested and taken to jail.
Losing control of their vehicle, the terrorist van driver was forced
to swerve into a Fox Photo stand on the edge of the parking lot. The
vehicle fell over and landed doorside down, trapping ...
Quite simply, the basis for their friendship is that Marty thinks Doc is cool, and Doc loves that someone thinks he's cool.
Co-Creator Bob Gale explains the backstory:
Okay, from the horse’s mouth (yes, I’m the horse — er, co-writer, co-creator): We never explained it in the movie. But the history of the characters that Bob Zemeckis and I created is this…
The movie never says specifically, but it may have been mentioned in the animated series. Marty declines to race against Needles, which did change the future. Marty and Jennifer's future did change after this event, but this was for the better.
Marty's involvement in the race had very negative consequences to his future life. He breaks his arm, and gives up ...
Yes, for as long as Marty is in 1885, there are two versions of the DeLorean there as well. However, that doesn't simplify things for them like you might think.
First, the gas. Couldn't they just get the gas from Doc's DeLorean and put it in Marty's? No, because when Doc hid the DeLorean in the cave, he expected the car to sit for the next 70 years. Because ...
It's from Back to the Future Part III. It happens in 1955 when 1955-Doc and Marty retrieve the DeLorean from the mine where 1985-Doc-in-1885 had hidden it.
Here's a clip of the scene on Youtube:
(Inspects the failed circuit) "Unbelievable that this little piece of junk could be such a big problem."
(Turns it ...
Well, the controls are 4-digit year. Because Y2K wasn't realized as a problem back then :)
So, presumably, even if the Flux Capacitor could take you anytime (as per @N_Soong's answer), you couldn't configure the controls outside of 0AD-9999AD year range.
Because if it never happened in Marty's experience, then Marty didn't completely fix the timeline.
Doc was envisioning what might have happened to the timeline now due to Marty's interference. He wouldn't know exactly, not knowing Marty as well as Doc would in 1985, but he'd know something was up. George would now be a different person, and make different ...
One theory is that the flux capacitor generated a portal through which the De Lorean traveled, and it could only remain open for a brief moment with the power available; by Doc's calculations, the length of that moment was exactly the amount of time it took for a De Lorean to travel its own length at 88 mph (that is, to enter the portal completely). A ...